Conveyor belting is typically formed from at least one reinforcing layer, a top cover and a bottom cover. The number of reinforcing layers varies depending upon the desired end use of the belting and the required strength characteristics. Belting length also varies due to the end use; for example, mining operations use belting with lengths measured in thousands of feet, while manufacturing operations may use belting with lengths of only several hundred feet. Whatever the ultimate end use, generally at some point the belting will need to be spliced, either in forming the endless belting from at least one belting section or when making repairs by removing a section of damaged or unserviceable belting.
Currently, vulcanizing splices are made at a bias or arch, with or without fingers at the joints of the splice. See e.g. U.S. Pat. Nos. 4,235,120; 4,279,676; 5,275,858; 5,377,818, 5,531,316, and 5,773,114. The outside joints may or may not be protected with breakers. Such a typical vulcanized splice is illustrated in FIGS. 3 and 4A. Illustrated is a three-ply conveyor belting 50. The ends 51 of the top cover 52 are spaced from each other and are cut at inclined, bias angles .alpha., .beta. with respect to both the longitudinal L and transverse T direction of the belt 50. The bottom, or pulley cover, layer 53 is prepared in an identical manner. The splices between the reinforcement layers 54, 55, 56, and the adjacent elastomeric layers, 57, 58 are spaced between the top and bottom cover layer splices. All of the splices are also cut at a bias angle .beta. relative to the transverse T direction of the belt. The edges of the reinforcement and elastomeric layers may be provided with fingers for interlocking the edges of the layers. Because all of the layers are spliced along a bias angle, the length of the splice S.sub.C is dependent upon the number of reinforcing layers and the splice inclination angle .beta.. The conventional spliced conveyor belting 50 is provided with breaker layers 59 to reinforce the splice and cover layers 60.
While the conventional method of belt splicing has proved adequate, there is still a loss of static strength in the belting at the splice location. Additionally, due to the inclination angles required of the conventional splicing, splicing of the belting can be time consuming, reducing operational time for the belting, and slowing down production whenever repair splicing is required. The present invention is directed toward overcoming these known drawbacks of the current splicing methods.
The inventive disclosed method of splicing multiple layers of belting improves the life performance of the splice in the high, medium, and light tension belt applications. The disclosed method of has the following benefits: a conventional bias is eliminated, consequently reducing the splice length and time required for splicing the belting; the load exerted on the splice will be symmetrically distributed about the centerline of the splice; the static strength of the splice is not compromised.